Free Telephony Project

For those who seek to create your own telephony sytem, this is for you
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The goal of this project is to build open telephony hardware and software, for example an embedded Asterisk box. Both the hardware and the software are open. You are free to copy and re use the hardware designs. The hardware for a complete embedded Asterisk IP PBX (including multiple analog/BR-ISDN ports or a T1/E1) can be built for $200 to $400 (much less in volume). Imagine an Asterisk-powered embedded IP-PBX in the form factor of a DSL modem - no PC required.
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http://www.rowetel.com/ucasterisk/